Page 35 - MDJ 2022 Jan-Jun, Volume 45 Number 1

Radiographic Assessment of the Technical Quality of Failed Endodontic Treatment Referred from General Dental Practitioners in
Pahang, Malaysia: A retrospective study

DISCUSSION showed that more maxillary teeth needed retreatment
(56.0 %, 70.3 %) than mandibular teeth (44.0 %, 29.7 %).
The study sample consisted of patients who were
referred to the Restorative Specialist Unit for the The endodontic practice of GDPs is mostly
management of failed root canal treatment. The majority confined to non-surgical root canal treatment of anterior
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of patients were referred from government dental clinics in teeth. Treatments for molar teeth are more challenging
Kuantan, as there are 10 government dental clinics because molars are multi-rooted and most canals are
available in this district. A number of patients were curved. Molar endodontics are seldom carried out at
referred from other districts in Pahang, as well as patients government dental clinics due to several limitations such
from the nearest state, Terengganu. These patients were as inexperienced operators, limited endodontic
referred to the Restorative Specialist Unit in Beserah armamentarium, lengthy treatment duration, and the
Dental Clinic as it was the only Restorative Specialist Unit limited availability of the dental chair due to the heavy
available in Pahang during this study period (2009–2017). number of outpatients in the government dental clinics.

Preoperative periapical (PA) radiographs were In the present study, 63.3 % of patients presented
used to assess the quality of root canal fillings. The with symptoms, while 36.7 % had none. This finding is
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commonly used PA radiographs are two-dimensional and consistent with the report by Hoen & Pink (2002), where
might not facilitate detection of relevant information in pain was noted in 51 % of failed endodontically treated
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orthogonal planes. As the quality of root canal filling was teeth. Root canal treatment can be carried out in the
determined only by evaluating its appearance on government as well as the private sector. Patients treated
radiographs taken in a bucco-lingual direction, this in our Restorative Department consist of those referred
limitation may result in error in evaluation of the length from private and government facilities. No study has been
and density of the root canal filling, particularly in done in Malaysia to compare endodontic treatments done
detecting the presence of voids. Cone-beam computed in private and government sectors. The higher percentage
tomography (CBCT) allows the tooth to be assessed three- (55 %) of initial treatment done in government clinics may
dimensionally and may have higher diagnostic yield as be due to the greater number of patients visiting the many
compared to PA radiographs when assessing the outcome government clinics available in the state of Pahang.
of root canal treatments, as it overcomes the diagnostic Another factor could be attributed to the cost involved
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limitations of the latter. when seeking treatment. There is a substantial difference
in cost for root canal treatment in private and government
The limitation encountered in this study is that the clinics.
information about the root-treated teeth were restricted to
the available data present in the referral letter and the case Studies evaluating the radiographic quality of
notes. The European Society of Endodontology (2006) root canal treatment were mostly based on the evaluation
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report recommends monitoring an endodontically treated of the length and the density of the root filling. 27–30 In this
tooth for a maximum of 4 years, to see if the radiographic study, the radiographic quality of root canal fillings was
appearance of periradicular tissues continues to improve evaluated based on the length, density, and the taper of the
within this time. However, data on exact treatment time of root canal filling. The percentage of root canal fillings with
the initial root canal treatment as well as pre- and post- adequate length was 43.6% in the present study, which was
operative radiographic records were not available, as the similar to results in the range of 40.7% to 60% in studies
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treatment took place at other dental health facilities. done in Belgium, Spain, and Denmark. However,
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Therefore, it was also unknown whether any improvement direct comparison between studies cannot be made
of the periapical status occurred after the initial root canal because the parameters used to score the radiographic
treatment. The decision for retreatment was made in cases length were not the same. Some authors 19,33 defined a 0–
with persistent clinical symptoms or in asymptomatic 2 mm distance from the end of the filling to the root apex
cases presenting with poor quality root canal filling if the as adequate, while others set this limit at 0–3 mm. 31,34 In
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tooth was a potential bridge abutment or planned for a post the Quality Guidelines for Endodontic Treatment, it is
or crown. stated that if the tip of the instrument during radiographic
root canal measurement is 3 mm away from the
As observed in this study, the tooth most often radiographic apex, there is no need for further working
needing retreatment was the maxillary incisor (53.3 %). length adjustments. In this study, the 0–2 mm threshold
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This differs from a study by Hoen & Pink (2002), which was considered adequate, as had been done in several more
showed maxillary first molars most often needing recent studies. 15,16 Teeth with flush root fillings had the
retreatment. The difference in our study may be due to the highest success rate followed by short and then long root
availability of root canal treatment for molar teeth in the fillings.
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early years of this study period, when such treatment was
limited to the Restorative Specialist Clinic only. Before The high percentage of inadequate length of the
2009, root canal treatments were limited to the anterior root canal fillings in this study (56.4 %) might indicate that
teeth in government clinics in Pahang. However, both there is lack of clinical thoroughness in terms of
studies (Hoen & Pink’s (2002) and the present study) determining and confirming the working length with
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periapical radiograph before starting the endodontic

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